A temperature‐mediated two‐step saccharification process enhances maltose yield from high‐concentration maltodextrin solutions

Abstract

BACKGROUND Designing a high‐concentration (50%, w/w) maltodextrin saccharification process is a green method to increase the productivity of maltose syrup. RESULTS In this study, a temperature‐mediated two‐step process using β‐amylase and pullulanase was investigated as a strategy to improve the efficiency of saccharification. During the saccharification process, both pullulanase addition time and temperature adjustment greatly impacted the final maltose yield. These results indicated that an appropriate β‐amylolysis in the first stage (the first 8 h) was required to facilitate saccharification process, with the maltose yield of 8.46% greater than that of the single step saccharification. Molecular structure analysis further demonstrated that a relatively low temperature (50 °C), as compared with a normal temperature (60 °C), in the first stage resulted in a greater number of chains polymerized by at least seven glucose units and a less heterogeneity system within the residual substrate. The molecular structure of the residual substrate might be beneficial for the subsequent cooperation between β‐amylase and pullulanase in the following 40 h (second stage). CONCLUSION Over a 48 h saccharification, the temperature‐mediated two‐step process dramatically increased the conversion rate of maltodextrin and yielded significantly more maltose and less byproduct, as compared with a constant‐temperature process. The two‐step saccharification process therefore offered an efficient and green strategy for maltose syrup production in industry. © 2020 Society of Chemical Industry

Designing liquefaction and saccharification processes of highly concentrated starch slurry: Challenges and recent advances

“…However, when the substrate concentration was increased to 40%-50%, the glucose yield decreased below 90%, and then a certain amount of isomaltooligosaccharide was produced (Qu, 2014). Li et al (2021) also found that maltose was the main product with a proportion of over 70% after the substrate concentration was controlled at 30% (w/w) in a traditional saccharification process. The saccharification solution with high substrate concentration (50%, w/w) yielded less maltose but more by-product than those from normal concentrations.…”

“…At the same time, the improvement of viscosity leads to low water activity, which again decreases the reaction efficiency. Li et al (2021) used 50% maltodextrin to produce malt syrup; they found that with the increasing substrate concentration, the maltose yield first increased and then decreased, indicating that the enzymatic efficiency and water mobility of the system decreased. Chen et al ( 2019) also reported similar experimental results.…”

“…The saccharification process (48 h) can be divided into two stages. In the complex enzyme reaction system, 50% of maltodextrin solution was hydrolyzed by β-amylase for 8 h, and then pullulanase was added to improve the maltose yield (Li et al, 2021). Taking 8 h after the reaction as the cutoff point when adding the pullulanase, the final yield of maltose was improved using the temperature mode from low temperature (50 • C) to high temperature (60 • C) (Yang, 2017).…”

“…Li et al. (2021) used 50% maltodextrin to produce malt syrup; they found that with the increasing substrate concentration, the maltose yield first increased and then decreased, indicating that the enzymatic efficiency and water mobility of the system decreased. Chen et al.…”

“…In recent years, highly concentrated starch sugar has attracted the attention of researchers or manufacturers because of its energy-saving and cost-control advantages, which is a developing trend in the starch sugar industry (Kong, Yang, et al, 2018;Wu et al, 2022). Various pretreatment methods and regulation strategies for highconcentration starch sugar production have been developed and reported in the last decade (Kong et al, 2021b;Li et al, 2016Li et al, , 2021. To the best of our knowledge, the design of liquefaction and saccharification processes of highly concentrated starch slurry has not been systematically reviewed.…”